There are significant differences between unions and free trade zones. Both types of trading blocs have internal agreements that the parties enter into to liberalize and facilitate trade between them. The key difference between unions and free trade zones is their approach to third parties [lack of ambiguity needed]. While a customs union requires all parties to apply and maintain identical external tariffs on trade with non-parties, parties to a free trade area are not subject to such a requirement. Instead, they can set and maintain any customs regime for imports from non-parties, as they see as necessary.  In a free trade area without harmonized external tariffs, the parties will adopt a system of preferential rules of origin to eliminate the risk of trade diversion [necessary ambiguities].  Most Swiss agreements are concluded under the European Free Trade Association (EFTA). In addition, Switzerland also has the right to negotiate free trade agreements without efTA participation, as has been the case, for example, with China, Japan and the Faroe Islands. A free trade agreement is a set of rules on how countries deal with each other when it comes to doing business together – importing and exporting goods, services and investment.
The world has achieved almost more free trade in the next round, known as the Doha Round Trade Agreement. If successful, Doha would have reduced tariffs for all WTO members overall. In general, trade diversion means that a free trade agreement would divert more efficient trade from out-of-area suppliers to less efficient sectors. Whereas the creation of trade implies the creation of a free trade area that might not otherwise have existed. In any case, the creation of trade will increase a country`s national well-being.  In principle, free trade at the international level is no different from trade between neighbours, cities or states. However, it allows companies in each country to focus on the production and sale of goods that make the best use of their resources, while others import goods that are scarce or unavailable domesticly. This mix of local production and foreign trade allows economies to grow faster and, at the same time, better meet the needs of their consumers. Both the creation of trade and the diversion of trade have a decisive impact on the establishment of a free trade agreement. The creation of trade will result in a shift in consumption from a cost producer to a low-cost producer, which will lead to an expansion of trade. On the other hand, trade diversion will mean that trade will move from a low-cost producer outside the zone to a more expensive producer in the free trade agreement.  Such offshoring will not benefit consumers under the free trade agreement, which will be deprived of the opportunity to purchase cheaper imported goods.
However, economists note that trade diversion does not always harm the overall national well-being: it can even improve national well-being as a whole if the volume of misappropriated trade is low.  Free trade agreements, which are free trade zones, are generally outside the multilateral trading system. However, WTO members must inform the secretariat when new free trade agreements are concluded and, in principle, the texts of free trade agreements are reviewed by the Committee on Regional Trade Agreements.  Although a dispute in free trade areas is not the subject of litigation within the WTO`s dispute resolution body, “there is no assurance that WTO panels will comply and reject jurisdiction in a particular case.”  Together, these agreements mean that about half of the goods arrive in the United States.